CVG, LEX, and SDF have, in my experience, been far more authoritarian than many other airports. CVG was the airport where CBP lined up everybody that was trying to leave by stopping the lines to hand in your Customs card, then walked two separate dogs down the lines. They then started accepting cards again, but it was a 10 minute delay.

They also engaged in retaliatory secondaries back before the shoe ban if you didn't voluntarily take the shoes off. "It's a random search, and maybe it'll teach you to follow our recommendations next time".